A continuing series of grisly murders has left Scotland Yard completely baffled. Horror Writer Edmond Bancroft is having a field day exploiting the crimes in his newspaper column, as well as mocking the authorities for their inability to capture the culprit. We quickly learn that nothing is as it seems to be with the author. Bancroft's obsession with horror and murder extends to a "Black Museum" of weapons of torture devices hidden away in the depths of his estate.